GZ 250 Forums - Snapped Timing Chain

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Re: Snapped Timing Chain

Quote:

Originally Posted by OldNTired

Quote:

Originally Posted by Water Warrior

WHAT is a good question. I would think you found an example of metal fatigue in one gear out of tens of thousands worldwide made for the GZ top end. Chance of this happening again are probably next to nil in the future for you and many other riders. It is unfortunate the gear broke but you were able to fix the engine using knowledge gained over the years. Many of us, including myself, would have been at the mercy of a dealer for repairs.

When I tore mine apart, I noticed that a couple of bolts (especially one of the two that hold the gear to the cam assembly) were a bit loose, and from what I could see had NO LocTite or similar product ever applied to it. All it would take is even a miniscule amount of excess vibration to loosen the bolt to the point where it would eventually wear (or bend) the lock plate; once the bolt works loose the other would loosen. Once loosened it would hit the side of the head and the pulley would be hit. That's not what happened to mine, but I could see it happen at some point way in the future, depending on miles driven and how you drive it.

If my typing seems like I'm falling asleep it's because I am. I just sat at the hospital for 1 1/2 days waiting for my grandson (the first) to come into this world. Ten lbs (screw the metrics!) one oz and about 2 feet long!

Re: Snapped Timing Chain

[quote=Water Warrior]

Quote:

Originally Posted by OldNTired

Quote:

Originally Posted by "Water Warrior":1ufc768e

That seems highly likely as the pics show a break right at a bolt hole. Thanks for mentioning your observation and solution with the Loc Tite.

Cogratulations on your 1st grandson. Must be a great feeling.[/quote:1ufc768e]

It is, it is, thank you. The three granddaughters are great, but there is something special about the Grandson.
As far as the bolts, my mistake, I should have mentioned them at the time. I was just too happy to get it running to mention all the 'little' things I came across. One of the bolts was one of those that holds the top of the engine mount to the frame - that sucker had worked loose almost a quarter inch! No LocTite, no locking nut.

Re: Snapped Timing Chain

One of the factory assembly workers must have been a little pissed on that day when he put your bike together, to try and get back at Suzuki, not you, but you bore the brunt of it.
Nice job in diagnosing and finding the problem, then getting it all back together.
Your son should be happy when he gets his bike back.